The National Weather Service in Missoula forecasts snowfall in Northwest Montana this weekend, especially over mountain passes, and the potential for periods of blowing snow and gusty winds. Temperatures are expected to plummet from the 40s and 50s to the teens and single digits by Sunday.

“Confidence remains high in an arctic front causing a host of impacts to west central Montana, southwest Montana, and north central Idaho (Idaho and Clearwater counties), scheduled to begin later this evening and last through Saturday,” the Weather Service reports. “Following the front, bitterly cold temperatures are expected by Sunday.”

Impacts are expected to be greatest along and closest to the Continental Divide, as well as over all area mountain passes, especially those crossing the Idaho and Montana border.

“While precipitation will begin as rain today (Friday), bitterly cold arctic air will settle in tonight and create a changeover to all snow, which could cause freezing of roadways and areas of ice beneath snow falling on top,” the Weather Service reports. “Mountain passes should see periods of very intense snowfall, causing significant impacts to travelers.”

Another concern will be very cold temperatures, especially Sunday morning.

“Given the mild temperatures in the 40s and 50s during the past few days, this arctic air will likely be felt even more so as a result,” the Weather Service said.